[Smad4 and TGF-beta1 expression and clinical significance in bladder transitional cell carcinoma]

To determine the expression of Smad4 and TGF-beta1 in bladder transitional cell carcinoma (BTCC), and to understand the mechanism of invasion, angiogenesis, and metastasis of BTCC.

The expressions of Smad4 and TGF-beta1 in samples of 42 human bladder carcinoma and 12 normal bladder mucosa tissues were determined with standard immunohistochemical analysis. We also analyzed the relationship among the expressions of Smad4 and TGF-beta1 and invasion, angiogenesis, and metastasis of BTCC, and the correlation between Smad4 and TGF-beta1.

The positive rate of Smad4 in BTCC was significantly lower than those in normal bladder mucosa tissues (33.3% vs 83.3%, P < 0.01). The expressions of Smad4 in poorly differentiated, invasive, recurrent, or with lymph node metastasis of BTCCs were lower than those in well differentiated, superficial, nonrecurrent, or without lymph node metastasis ones (P <0.05). The positive rate of TGF-beta1 in BTCC was significantly lower than that in normal bladder mucosa tissues (64.3% vs 100%, P <0.01), which was positively correlated to that of Smad4 (P = 0.000).

The expressions of Smad4 and TGF-beta1 in BTCC decrease with the increase in clinical stage, poor pathological grade, and the recurrence and metastasis of BTCC.